This invention generally relates to automatic door openers, and more particularly to a linear drive power door operator for selectively and automatically opening and closing a door swingably mounted on a door jamb.
In 1991, rules promulgated pursuant to the Americans with Disabilities Act (ADA) require that certain public buildings must remove barriers and provide people with disabilities access equal to, or similar to, that available to the general public. One area covered by these rules is the provision of accessible door openings. The ADA requires, among other things, door openings at least thirty-two inches wide, easily manipulated door handles, a maximum opening force for opening doors, a minimum closing time, and doors capable of opening at least ninety degrees. Automatic door openers have been developed in order to meet the standards set by the ADA and to give people with disabilities equal access to buildings.
The present invention is in the same general field as the door assister disclosed in U.S. Pat. No. 4,040,144 to Lasier et al. and represents improvements thereover. The door assister disclosed in this patent includes a rack and pinion arrangement for lessening the force required to open a door. More particularly, the door assister includes a pneumatic and hydraulic arrangement which powers the rack when a person applies a small opening force on the door for reducing the opening force required to open the door. One problem associated with this type of door opener is that due to its relatively complex nature (i.e., in that it requires pneumatic components, including a compressor), it is relatively expensive to assemble and install.
The foregoing illustrates limitations known to exist in present door opening and closing assemblies. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.